Adolf schikner



(N0 ModeL) A. SGHIRNER. HOLDER FOB INOANDESCENT ELECTRIC LAMPS. 3'71.

, Patented July 29, 1890.

Fig.1.

UNITED STATES PATENT OFFICE.

ADOLF SOHIRNER, OF BERLIN, GERMANY.

HOLDER FOR INCANDESCENT ELECTRIC LAMPS.

SPECIFICATION forming part of Letters Patent No. 133,371, dated July 29, 1890. Application filed March 31, 1890. Serial No. 346,035. (No model.)

T0 to whom it may concern.

Be itknown that I, ADOLF SCHIRNER, a subject of the King of Prussia, residing at Berlin, Kingdom of Prussia, Germany, have invented anew and useful Improvement in Holders for Incandescent Electric Lamps, whereof the following is a specification.

My invention relates to holders for incand escentelectric lamps havinga screw-threaded sleeve, into which the lamp is screwed with its mounting, provided with a corresponding outside thread. Lamp-holders of this kind present the inconvenience that the lamps often become loose therein from concussions, and that they are apt to be injured on being screwed down too tightly. In view of obviating these inconveniences I impart to the sleeve of the holder such resiliency that it permanently exercises a moderate pressure from all sides on the screw-threaded mounting of the lamp, and that if the lamp is screwed in with too much force the sleeve yields peripherally and allows the threads of the mounting to slip over from the first engaged threads of the sleeve to the preceding ones. For this purpose I render the metal from which the sleeve is made as resilient as possible, and I cut into the sleeve a number of longitudinal slits, which divide it into as many segments or lobes, being at their base in connection with the remaining part of the holder. In order to increase the elastic pressure with which the segments bear against the mounting, a separate spring or springs may be combined with the former.

In the annexed drawings a lam p-holder carried out according to my invention is represented by Figure 1 in elevation and by Fig. 2 in a view from below. Fig. 3 shows a portion of the lamp with the mounting thereof.

In Fig. 1, a is the sleeve of the holder, made as usual of sheet metal, and having screwthreads embossed therelnto, the metal em ployed for the manufacture of the sleeve being hardened so as to render it elastic. Into the sleeve are cut the slits 0, Figs. 1 and 2, by which the segments or lobes b are produced. At its rim the sleeve is provided with two collars f, also divided by the slits c and constituting a groove, into which is placed the spiral spring 6, having its ends connected togethcr, so that it forms an elastic ring encircling the segments 1).

In order that the holder may fully answer its purpose, the parts have to be constructed in such manner that the segments 5 exercise a pressure against the mounting (Z, Fig. 3,

from the beginning of its being screwed in, and that they be not strained over and above their resiliency in case a slipping over of the threads occurs.

I claim as my invention- 1. In a holder for incandescent lamps, the combination of a sleeve made of resilient sheet metal andwith screw-threads embossed thereinto, the said sleeve being provided with longitudinal slits whereby it is divided into segments, and a spring or springs acting on the said segments, substantially as specified.

2. In a holder for incandescent lamps, the combination of a sleeve made of resilient sheet metal and with screw-threads embossed thereinto, the said sleeve being provided with longitudinal slits whereby it is divided into segments and having a groove at its rim, and an annular spiral spring placed in said groove, substantially as set forth.

In testimony whereof I have hereunto set my hand in the presence of twosubscribing witnesses.

ADOLF SCI-IIRNER. Witnesses:

EUGEN KAYSER, L. WILMs. 

